^? THE NAUTILUS 101(3):101-110, 1987 Page 101 Anatomy and Systematic Position of Fastigiella carinata Reeve (Cerithiidae: Prosobranchia) Richard S. Houbrick National Museum of Natural History Smithsonian Institution Washington. DC 20560, USA Robert Robertson The Academy of Natural Sciences 19th and the Parkway Philadelphia, PA 19103, USA R. Tucker Abbott American Malacologists, Inc. PO Box 2255 Melbourne, FL 32902, USA ABSTRACT Fastigiella carinata is placed in the family Cerithiidae, close to the genus Pseiidooertagus Vignal on the basis of conchologi- cal, radular, and anatomical characters. Fastigiella has a shell sculptured with three strong spiral cords, an aperture with a distinct anterior canal, a pseudumbilicus, missing in juveniles, and a siphonal fasciole. The operculum is ovate, corneous, and paucispiral with an eccentric nucleus, and the radula is tae- nioglossate. The animal has an unusual hypobranchial gland comprised of many transverse leaflets, a ridge dividing the anterior oviductal groove, and an open pallia! oviduct with the seminal receptacle in the medial lamina of the posterior ovi- duct. INTRODUCTION The systematic relationship of Fastigiella carinata Reeve, 1848 to other prosobranchs has been uncertain and spec- ulative since its description nearly 140 years ago. The genus has been thought to include only one living species and until now was known only from empty shells from the central Bahamas and northwestern Cuba. Even its faimilial relationships have been in doubt. Fastigiella Reeve has been a puzzle to many workers. Reeve (1848) remarked in the original description that the shell i?i?itermediate between Turritella Lamarck and Cerithium Brugui?re, but he hinted that Fastigiella might be a Buccinum-like carnivore {i.e., what would now be called a neogastropod). Reeve placed Fastigiella in the catch-all "family Canal?fera" because of its char- acteristic anterior canal. Woodward (185L129) placed it with a query after "Nerinaea" in the family "Cerithi- adae" (= Cerithiidae sensu lato). H. Adams and A. Adams first placed Fastigiella in the Fasciolariidae (1853:155) but later in the Cerithiidae (1858:655). Chenu (1859:182) also assigned Fastigiella to the Fasciolariidae. VIost later malacologists have followed Woodward and H. Adams and A. Adams in placing Fastigiella near Cerithium in the Cerithiidae, albeit in some cases with doubts indicated. Concepts of the genus Cerithium and of the family Cerithiidae have been various and generally broad. Opinions on the relationships of Fastigiella within the superfamily Cerithiacea and related superfamilies (as presently conceived) have also been varied. For ex- ample, M?rch (1877:209), although placing Fastigiella near Cerithium {sensu lato), stated that Fastigiella is closest to a Recent "Triphoris" (= Triphora Blainville; Triphoridae) and to a Pliocene "Cerithium" (assigned by Wenz, 1940, to the Potamididae). More orthodox dis- cussions and placements of Fastigiella are those of Fisch- er (1884:679), Tryon (1887:115,149), Thiele (1929:214), P?rez Farfante (1940:71), Wenz (1943:770), and Saras?a and Espinosa (1977:2). Ford (1944:8) considered Ceri- thidea Swainson, 1840 (Potamididae) a subgenus of Fas- tigiella, which is incorrect nomenclaturally {Cerithidea having priority over Fastigiella). Moore (1971:1-2), on the basis of its rarity and the presence of a siphonal fasciole and prominent varices on the shell, suggested that Fastigiella is a neogastropod, probably belonging to the Fasciolariidae. Abbott (1974:105), while assigning Fastigiella to the Cerithiidae, wrote that "it may prove to be in a totally different family, possibly the Pyrami- dellidae." Approximately 100 specimens are now found in mu- seums and private collections. Hugh Cuming possessed the first known specimen as early as 1847, but recorded no locality data. Dr. C. M. Poulsen obtained an immature specimen from Eleuthera prior to 1877 (F. poulseni M?rch, 1877; herein regarded as a synonym). The Amer- ican Museum of Natural History has a dataless specimen from a collection catalogued prior to 1900. The Rev. P. D. Ford collected several specimens in 1943 along the north coast of New Providence Island. From 1953 through 1986 several dozen specimens have been reported in the literature or have been collected by amateur concholo- gists. All collectors have found dead specimens from beach drift or in water less than 3 m in depth. Recently, a living Fastigiella was collected by Joseph Lleida at New Providence Island, Bahamas, and pre- served in alcohol. This specimen (USNM 859097), al- though not preserved well enough for histol?gica! study, was a mature female that provided an operculum, radula and preserved soft parts suitable for general anatomical study. Page 102 THE NAUTILUS, Vol. 101, No. 3 MATERIALS AND METHODS The senior author studied the anatomy, radula, and oper- culum of a live-collected snail and also assembled some distribution records. Conchological studies, nomencla- tural history, and geographic data are by the junior au- thors, Robert Robertson and R. Tucker Abbott. The following abbreviations are used throughout the text: AMNH, American Museum of Natural History; ANSP, Academy of Natural Sciences, Philadelphia; DMNH, Delaware Museum of Natural History; BM(NH), British Museum (Natural History); LACM, Los Angeles County Museum of Natural History; USNVI, National Museum of Natural History, U.S. National Museum, Washington, DC. Material examined: BAHAMAS; Nassau, New Providence Id. (LACM S1855); Brown's Point, Nassau, New Provi- dence Id. (DMNH 65992, 65993; USNM 707161, 859097); Silver Cay and Hog Id., off Nassau, New Providence Id. {fide G. Fehling); Delaports Point, Clifton Pier, east end of Goulding Cay, New Providence Id. (D. Cosman, leg.); South West Reef, 7 mi south of New Providence Id. (D. Cosman, leg.); Cable Beach, New Providence Id.; Holms Cay, Berry Ids. (J. Cordy collection); mouth of Stafford Creek, east Andros Id. (DMNH 49248); off Small Hope Bay, east Andros Id. (DMNH 29236, 40987, Sue Abbott, leg.); Cowrie Reef, Andros Id. (DMNH 51344); Cave Cay, Exumas (D. Cosman, leg.); Guana Cay, Exumas (D. Cosman, leg.); Highburn Cay (J. Cordy, leg.); Sail Cay (G. Duffy, leg.); Wemys Bight, Eleuthera (AMNH); Mil- lars, Eleuthera (M. McNeilus, leg.); Berry Islands, Eleuthera (fide R. Houbrick); Windemere Id., Eleuthera (AMNH); Governor's Harbour, Eleuthera (AMNH); Bot- tle Cay, Schooner Cays, Eleuthera (ANSP 189519); Pow- ell's Point, Eleuthera (DMNH 51837); west coast of Cat Island (W. G. Lyons, in litt.). CUBA: Cardenas (USNM 434792); off Havana (Jaume collection); Santa Fe, 8 km west of Marianao, Havana (I. P?rez Farfante, leg.); Co- macho Beach, 4 mi west of Varadero, Matanzas (J. Fin- lay, leg.); (DMNH 105578); Varadero Beach, Matanzas (J. Finlay collection; Museo Poey, fide Jaume & Saras?a, 1943; ANSP 316919); Camarioca Reef area. Matanzas (J. Finlay, leg.); Bah?a de Matanzas (R. Burquete, leg.). A live-collected, mature, female snail was collected May, 1986 by Joseph Lleida at Brown's Point, New Prov- idence, Bahamas, where it was found living in shallow water. The specimen, which had a shell 32.1 mm long and 11 mm wide, was preserved in 70% EtOH. It was kindly given to one of us, R. Tucker Abbott, and sent to the senior author for anatomical studies. The soft parts were extracted by breaking the shell in a small vise. The animal was dissected under a binocular dissecting mi- croscope. Shell pieces, apex, operculum, and radula were examined using a Zeiss Novascan-30 scanning electron microscope. This specimen and its parts (USNM 859097) are deposited in the National Museum of Natural His- tory, Smithsonian Institution. RESULTS SYSTEMATIC DESCRIPTION Family Cerithiidae Fleming, 1822 Subfamily Cerithiinae Fleming, 1822 Genus Fastigiella Reeve, 1848 Genus Fa.sligiella Reeve, 1848:14-15. Type-species: Fastigiella carinata Reeve, 1848, by monotypy. Diagnosis: Shell large, turreted, high spired, sculptured with 3 major, strong, raised spiral cords per whorl, ex- clusive of body whorl. Aperture ovate, about Vi the shell length, and with short, recurved anterior canal. Pseud- umbilicus and siphonal fasciole present on mature adults. Taenioglossate radula with lateral teeth having large bas- al plate and long lateral extension; marginal teeth long, hook-like. Paired saffvary glands in front of nerve ring. Hypobranchial gland comprised of many transverse leaf- lets. Strong longitudinal ridge bisects distal oviductal groove of palliai oviduct. Remarks: Various fossil species have been referred to Fastigiella [e.g., by Cossmann, 1906:93-95). The only one appearing to us as possibly belonging in the genus is "Cerithium" rugosum Lamarck, 1804, of the Middle Eocene of France. Mellevillia Cossmann, 1889, named as a Lower Eocene "section" of Fastigiella from France, has none of the characteristics of the genus. The Eocene fossil, Zefallacia australis (Suter, 1919) somewhat resem- bles Fastigiella. Fastigiella is a monotypic genus restricted to a small area of the western Atlantic, i.e., the central Bahamas and northwestern Cuba. Its closest relatives appear to be in the cerithiid genus Pseudovertagus Vignal, which is now confined to the Indo-Pacific. "Fastigiella" squamu- losa Pease, 1868, from the Tuamotus (Polynesia), is a high-spired Recent Coralliophila species. Figures 1-5. Fastigiella carinata Reeve from Holms Cay, Berry Islands, Bahamas. Note light tan spiral band adjacent to suture. Length 44.4 mm (J. Cordy collection). L Apertural view showing anal fasciole and pseudumbilicus. 2. Lateral view, showing configuration of outer lip. 3. Basal view, showing reflected anterior canal and basal sculpture. 4. Dorsal view. 5. Dorsal view of shell whitened with ammonium chloride to enhance sculptural details. Figures 6-8. Fastigiella carinata, juvenile from Nassau, New Providence Id., Bahamas. Length 12 mm (]. Lleida collection). 6. Scanning electron micrograph of early whorl sculpture of specimen in figure 8 (protoconch missing). 7. Detail of midwhorl sculpture of shell in figure 8. 9. Upper whorls of Pseudovertagus aluco Vignal, showing early sculpture similar to that of adult Fastigiella. Total shell length 79 mm. Figures 10, 11. Scanning electron micrographs showing microscopic spiral striae (fragments of USNM 859097). 10. Scale bar = 200 ^m. 11. Close up of spiral striae showing microscopic cancellate sculpture of striae. Photograph turned 90 degrees; scale bar = 600 urn. R. S. Houbrick ei ai, 1987 Page 103 Page 104 THE NAUTILUS, Vol. 101, No. 3 Fastigiella carinata Reeve FasHgiella carinata Reeve, 1848:15, 1 fig. Type-locality un- known; subsequently selected: Eleuthera, Bahamas (Sara- s?a and Espinosa, 1977:4); twosyntypes: BM(NH) 1986272; 1860:122-123, Woodward, 1851:129; H. Adams and A, Adams, 1853:155,655, pi. 16, fig. 7; Chenu, 1859:182, fig. 916; Tryon, 1882:249, pi. 70, fig. 64; pi. 10, fig. 46; Thiele, 1929:214; Wenz, 1943:770, fig. 2230; Pilsbry, 1953:77-78, pi. 6, figs. 2, 3; Kline, 1953:142; Jensen, 1968:6-7, fig.; Abbott, 1974:105, fig. 1009; Saras?a and Espinosa, 1977: 1-11, fig. 1; Abbott and Dance, 1982:68, fig. 6. Fastigiella poulseni M?rch, 1877:207-208. (Type-locality: Eleuthera, Bahamas; holotype: an immature shell without a pseudumbilicus.) Poulsen, 1878:9, no. 533; P?rez Far- fante, 1940:71, pi. 13, fig. 3; Jaume and Saras?a, 1943:57. FasHgiella (Cerithidea) carinata Reeve. Ford, 1945:8. Description: Shell description (figures 1-8,10,11): Shell length 11.2-48.4 mm [mean 33.0 mm; n = 16; observed up to 53.2 mm in Cuba (Saras?a & Espinosa, 1977:5, 11)]. Spire high; spire angle 25-35 degrees (mean 28 degrees). Shell fairly thin to thick, white, sometimes with brownish orange or light tan spiral band (figures 1, 2, 4). Periostracum inconspicuous, but scale-like when viewed microscopically (figures 10, 11). Protoconch unavailable (shell prone to decollation). Teleoconch whorls 11.7 + . Teleoconch initially with a subsutural ramp and 3 spiral cords, the uppermost forming a slight shoulder (figures 6, 7). Upper whorl cords with slight nodes or prickles caused by weak, regularly spaced axial growth wrinkles. Lower whorls of large shells with increasing number of spiral cords (figures 1-5), the new ones beginning as intercalations. Subsutural ramp becoming a wide, slightly raised cord accompanied below by a smaller cord. All other cords larger and about equal-sized on large shells. Counting all 3 kinds of cords, there are 11-14 on last whorl of large shells. Fine spiral threads on all cords and interspaces (figure 10). Pair of subperipheral keels absent on small shells. Suture slightly impressed. Several irreg- ularly spaced faint varices present on lower whorls of large shells (figure 3). A short, somewhat recurved but deeply incised anterior canal present (figures 1, 3, 8). On small shells its left edge is a slightly raised spiral fold joining the columella distally; on large shells a faint swell- ing in its place (figure 1). Anterior canal variable in width (averaging fairly wide) and, after shell attains length of about 25 mm, leaving a spiral siphonal fasciole with strong growth lines (figure 3). A pseudumbilicus (figure 1) of variable width (up to 1.3 mm) and morphology develops after shell reaches length of about 25-35 mm. Parietal callus thin, conforming with underlying cords on small shells; on large shells callus thick and not con- forming, so that there can be 1-3 false umbilical chinks formed by cord interspaces to produce a siphonal fas- ciole. Faint, wide posterior canal present on large shells, viewed aperturally (figure 1). Columella roundly con- cave. Outer hp thin in juveniles and thick on large shells; no thick peritreme callus, eversi?n of outer lip, or up- turned suture near outer lip. External anatomy (figure 18): Adult female (shell 32 mm long) body slender, tapering, and comprising 6 or 7 whorls. Animal whitish with tiny red dots on head- foot. Head has conspicuo.usly large, broad, spade-shaped snout, bilobed at the tip (figure 18, sn). Pair of stubby cephalic tentacles and tiny black eye at peduncular base of each tentacle (figure 18, t). Foot thick and muscular. Propodial mucus gland (figure 18, mg) is a deep slit along leading edge of anterior sole. Sole composed of thick, hard, yellowish tissue thrown into lumps. Large, dark brown, horny operculum (figure 17) thick, ovate, pau- cispiral with subcentral nucleus and filling the shell ap- erture. Columellar muscle (figure 18, cm) thick and short, about V2 mantle cavity length. Mantle edge thick and dorsally fringed with short papillae (figure 18, mp). In- halant and exhalant siphons inconspicuous except for slight thickening of mantle edge. Posterior 5 whorls com- prise digestive gland (figure 18, dg), which is overlain by ovary (figure 18, ov). The 2 whorls above body whorl accommodate the kidney (figure 18, k) and stomach (fig- ure 18, st), respectively. Mantle cavity: Mantle cavity deep and spacious, oc- cupying about 2.5 whorls. Osphradium (figures 19, 20, os) a raised ridge, squarish in cross section, darkly pig- mented and probably highly ciliated on each side. Os- phradium begins about 2 mm behind distal end of ctenid- ium and extends for % ctenidial length. It fies closely adjacent to ctenidium, but deviates from it in region of inhalant siphon. Ctenidium (figures 19, 20, ct) a narrow, large, well-developed organ comprising long, triangular filaments with finger-like tips. Each filament has a sup- porting rod along its leading edge. Hypobranchial gland (figures 19, 20, hg) a highly developed, thick organ com- prising a series of thin, transparent, semicircular leaflets that run adjacent to ctenidium and extend length of mantle cavity. Spaces between each leaflet filled with flocculent, acellular mucus-like material that may be se- creted by epithelial lining of leaflets. Rectum (figures 19, 20, r) tubular and thick, filled with rod-shaped fecal pellets without sand and consisting of detritus. Alimentary tract: Broad, spade-shaped snout (figure 18, sn) highly muscular and bearing relatively large buccal mass. Pair of small, semilunar, chitinous jaws comprising many small, overlapping scales at tip of buccal mass. Figures 12-17. Scanning electron micrographs of radula and operculum of Fastigiella carinata (USNM 859097). 12. View of part of radular ribbon with marginal teeth spread out. Scale bar = 125 ^m. 13. Half row of teeth showing long lateral tooth and narrow hooklike marginal teeth. Scale bar = 63 ixm. 14. Detail of rachidian tooth, showing basal plate and cusps of rachidian and lateral teeth. Scale bar = 25 ixm. 15. Tips of marginal teeth showing small denticles. Scale bar = 19 ^m. 16. Rachidian and lateral teeth showing long lateral-basal extensions of lateral teeth. Scale bar = 43 ?xm. 17. Operculum. Length 8.4 mm. R. S. Houbrick et al, 1987 Page 105 Page 106 THE NAUTILUS, Vol. 101, No. 3 cme cm 19 hg ct cod Figures 18-21. Anatomical features of FasHgiella carinala. 18. External features of female viewed from the right. 19. Schematic representation of cross section behind nerve ring showing morphological relationships of major mantle cavity organs. 20. Schematic representation of section of mantle cavity organs exclusive of palliai gonoduct showing relationship of hypobranchial gland leaflets to rectum and ctenidium. 21. Schematic representation of palliai oviduct and its internal components, ag = albumin gland; cm = columellar muscle; cme = cut mantle edge; cod = coelomic oviduct; ct = ctenidium; dg = digestive gland; es = esophagus; f = fusion of lateral and medial laminae; ft = foot; hg = hypobranchial gland; k = kidney; 11 = lateral lamina; mc = mantle cavity; mg = mucus gland; ml = medial lamina; mp = mantle papillae; op = operculum; os = osphradium; ov = ovary; ovg = oviductal groove; po = palliai oviduct; r = rectum; rd = central ridge dividing anterior oviductal groove; sg = sperm gutter; sn = snout; sr = seminal receptacle; st = stomach; t = cephalic tentacle. R. S. Houbrick et al., 1987 Page 107 Buccal mass has long odontophore. Salivary glands con- sist of pair of weakly coiled tubes that originate in front of nerve ring and empty at dorsal anterior part of buccal mass near jaws. Salivary glands thicker anteriorly. Mid- esophagus slightly expanded and has large dorsal food channel. Large stomach occupies about 1.5 whorls and comprises short style sac, hyaline gastric shield, large central pad-like ridge, and enormous sorting area. Radula (figures 12-16): Taenioglossate radula short, about Vi? shell length (L = 2.2 mm), and comprises around 280 tranverse rows of teeth. Rachidian tooth wider than high, with convex tip and squat, hourglass-shaped basal plate (figure 14). Cutting edge of rachidian tooth com- prises central cusp flanked on each side by 3 smaller denticles. Lateral tooth conspicuously large with very long lateral extension of basal plate and weak central buttress that extends posteriorly (figure 16). Cutting edge of lateral tooth serrated with 2 or 3 inner denticles, a large, pointed central cusp, and 4-6 outer denticles (fig- ure 14). The two marginal teeth (figures 13, 15) are narrow, elongate, curved hooks with pointed tips and are wider where attached to basal radular membrane. Outer marginal tooth slightly larger and less hooked than inner one. Marginal teeth serrated near their distal outer sides with 3-5 tiny, sharp denticles (figure 15). Reproductive tract: Large, acinous ovary (figure 18, ov) overlies digestive gland and occupies the first 4 or 5 whorls. It appears to consist of large cells. Female palliai oviduct (figures 19, 21) a very long open tube, comprising lateral (figures 19, 21, II) and medial (figures 19, 21, ml) laminae connected to mantle floor along their dorsal mar- gins. Posterior end of palliai oviduct has thickened walls and is closed by fusion of the 2 laminae (figure 21, f). Thick albumen gland (figure 21, ag) at posterior end of palliai oviduct. Seminal receptacle (figure 21, sr) and sperm gutter (figure 21, sg) lie near posterior end of medial lamina. Oviductal groove (figure 21, ovg) formed at thick, glandular, connecting bases of these 2 laminae. Oviductal groove divided along its length by large, cen- tral ridge (figure 21, rd) that begins anteriorly and ex- tends back a little past midpoint of palliai oviduct. Ridge tapers and ends just anterior to opening of sperm gutter to seminal receptacle on medial lamina. This ridge ef- fectively divides anterior and median parts of the oviduct into 2 open chambers, 1 of which may function as sper- matophore bursa. Male gonoduct unknown. Nervous system: Nervous system epiathroid. Cerebral ganglia joined by short, but distinct, connective. Right pleural ganglion joined to right cerebral ganglion by short connective. DISTRIBUTION AND ECOLOGY Distribution (figure 22): Fastigiella carinata is known only from the Great Bahama Bank and the northwestern coast of Cuba. The known distribution in Cuba is from Santa Fe, 8 km west of Marianao, Habana, west to Car- denas (P?rez Farfante, 1940:71, pi. 13, fig. 3; Saras?a & Figure 22. Geographical distribution of Fastigiella carinata based on available records, showing disjunct range. Espinosa, 1977; USNM 434792), a coast?ne only about 140 km long that is not the nearest part of Cuba to the Bahamas. Although previously published Bahamian rec- ords were from Andros and Eleuthera only, Fastigiella has been found on the eastern coast of Andros Island; the northern coast of New Providence Island; the Berry Islands; the southwestern coast of Eleuthera and the near- by Schooner Cays; Cat Island; Exuma Cays. This species appears to be absent from the Little Bahama Bank. Fastigiella carinata seems to be fairly rare in the lo- calities discussed above, but may ocur in other parts of the Bahamas and Cuba that are not as conchologically well known. Saras?a and Espinosa (1977), who knew of 13 Cuban and only three Bahamian shells, stated that the species is more common in Cuba than in the Bahamas. We have been able to study many Bahamian and only 3 Cuban shells. Like such other shallow water species as Cittarium pica (Linnaeus) and Turbinella angulata (Lightfoot), this Bahamas-Cuba species has not been re- ported in Florida or Bermuda. Ecology: Not much can be said about the ecology of Fastigiella. All of the shells available to us are slightly to moderately decollated (figures 6, 7), with not even part of a protoconch present. As the smallest intact whorl width is 0.7 mm, larval development could be plankto- trophic or lecithotrophic. Although spawn and larvae remain unknown, the restricted geographic range sug- gests lecithotrophy or direct development. The single, live-collected female described herein was found after a five-day blow, intertidally in a small hole on a rocky shelf bordering deeper sand and grass banks. As only one living specimen has been found, it is not certain that this is the normal habitat. Frequently, empty shells are inhabited by hermit crabs which also occur in other shallow water species such as Tegula fasciata (Born) and Cerithium litteratum (Born). The alimentary tract and fecal pellets indicate typical cerithiacean algal-de- trital herbivory. Page 108 THE NAUTILUS, Vol. 101, No. 3 DISCUSSION Shell variation: This species does not display the mor- phological variation that is so common among cerithiid genera such as Cerithium, Clypeomorus Jousseaume, and Rhinoclavis Swainson. Nevertheless, there are some variations that should be noted. Newly dead specimens may have a light tan spiral band adjacent to the suture (figures 1, 2, 4). Saras?a and Espinosa (1977:6-7) re- corded remnants of a brownish orange color pattern on some Cuban shells. Differences between fully grown and immature shells are most pronounced in the columellar and siphonal areas of the body whorl. Immature shells (figure 8) lack the pseudumbilicus and siphonal fasciole that is present in fully grown specimens (figures 1-3). The narrow pseud- umbilicus, which varies in width, and the siphonal fasciole develop after the shell reaches a length of 25-35 mm, as noted by Jensen (1967). Several Cuban shells reach a length of 52-60 mm, while the largest Bahamian specimens observed are 45- 48.4 mm. Fully mature specimens from Cuba, exceeding 35 mm in length and having a deep, narrow pseudum- bilicus, differ in having six or seven evenly-sized spiral cords on the penultimate whorl, while those from the Bahamas have only three or four cords. We do not believe that this geographical difference is worthy of subspecific recognition. Cuming's specimen, illustrated by Reeve (1848:15) and copied by Woodward (1851), Tryon (1882), Wenz (1943), and others, is evidently a Bahamian spec- imen. Comparative conchology: Before the live-collected specimen became available for study, one of us (Rob- ertson) noted similarities between the shells of full-grown Fastigiella and young Pseudovertagus Vignal, a genus that has been monographed by Houbrick (1978:99-120). In the Recent fauna, Pseudovertagus is restricted to the tropical Indo-Pacific, where there are four species. Hou- brick classified Pseudovertagus in the family Cerithi- idae, subfamily Cerithiinae. Although full-grown shells of Pseudovertagus and Fastigiella are dissimilar, the sculpture of their upper whorls is very similar. The upper whorls of Fastigiella carinata (figures 6, 7) and Pseu- dovertagus aluco (Linn?) (figure 9) are illustrated here. Both have three or four main spiral cords per whorl; the cords are prickly or noded; a subsutural ramp is faint to well-developed, and the whorls may or may not be slight- ly shouldered by one of the cords. Pseudovertagus and Fastigiella are the only living cerithiaceans known by us to have this apical sculpture. Cerithium nodulosum Brugui?re, 1792, of the Indo-Pacific, is anomalous within its genus by having apical sculpture intermediate be- tween that of Cerithium sensu stricto and those of Pseudovertagus and Fastigiella. This suggests that these three genera may be fairly closely related. Pseudovertagus undergoes much greater ontogenetic sculptural change than Fastigiella. Fastigiella may be a neotenous relative to Pseudovertagus. Adults of the two genera both lack a prominent fold on the middle of the columella such as is present in species of Rhinoclavis, an Indo-Pacific genus close to Pseudovertagus (see Hou- brick, 1978). The outer fip (viewed laterally) is not sin- uous in either Fastigiella (figure 2) or Pseudovertagus, as it is in Claoocerithium Cossmann, another genus close to Pseudovertagus (see Houbrick, 1978). Pseudovertagus is not congeneric with Fastigiella as there are a number of conchological and anatomical autapomorphies distin- guishing the latter taxon (see "Conclusion"). There are a few vague resemblances between Fastig- iella and Campanile Fischer (Cerithiacea: Campan- ilidae), of which one relict species occurs in southwest Australia (Houbrick, 1981a). There are two Eocene species of Pseudovertagus in France, and two Miocene and Plio- cene species in Florida (Houbrick, 1978:116-120), close to Fastigiella's range. Comparative anatomy: Study of the radula and anat- omy has done much to clarify the systematic position of Fastigiella. Although only a single, poorly preserved specimen was studied, it was a sexually mature female and provided most of the important characters essential for comparison with other cerithiacean taxa. Externally, the snail removed from its shell looks very much like some members of the Cerithiidae, such as Cerithium, Rhinoclauis, and Pseudovertagus. Notable features are the broad, bilobed snout, small cephalic ten- tacles, and tiny eyes (figure 18). The broad snout, con- tracted by preservation, is probably long and extensible in a living snail. In its contracted state it resembles those observed in Diastoma (Houbrick, 1981b:603, fig. 2) and Campanile Deshayes (Houbrick, 1981a:269, fig. 3, a, b), some Cerithium species, and especially Pseudovertagus. The mantle edge, fringed with small papillae (figure 18, mp), and the large, thick operculum (figure 17) are typ- ical of those observed in cerithiids. The sole of the foot, particularly the anterior portion, was composed of thick, yellowish, hard tissue. This may be an unusual feature of Fastigiella foot morphology but is more likely an artifact of preservation. Many cerithiaceans have a cil- iated groove or ovipositor on the right side of the foot, but no trace of these structures was seen in Fastigiella. The mantle cavity is quite deep and typically ceri- thiacean in organization. The osphradium appears to be a raised ridge with wrinkled sides. It does not resemble the osphradium of cerithiid species of comparable size, but is more like those seen in potamidids, modulids, and thiarids. An important character is the unusual hypo- branchial gland, which comprises a long row of trans- verse, thin, transparent leaflets and resembles a secondary ctenidium (figure 20, hg). Between the leaflets is thick mucus-like, flocculent, granular material. Due to the poor preservation of the animal, it was not determined if this material was formed by a breakdown of the epithelial lining of the leaflets or was merely hypobranchial gland secretion. The hypobranchial gland is unlike those of all other known cerithiaceans except Pseudovertagus species (family Cerithiidae), which have a nearly identical hy- pobranchial gland (Houbrick, personal observation). The hypobranchial gland of Cerithium nodulosum has prom- R. S. Houbrick ei al., 1987 Page 109 inent raised transverse ridges and may be a transitional stage before the development of leaflets as found in Fas- tigiella and Pseudovertagus (Houbrick, personal obser- vation). The hypobranchial gland of Campanile also has leaflets, but they are tiny and comprise many parallel rows (Houbrick, 1981a:274, fig. 4, A, Ihg). This gland is thus a much different structure in Campanile and its leaflet structure is not considered homologous with that seen in Fastigiella. The palliai oviduct is a typically cerithiacean open duct. There is no spermatophore bursa, but its function may be taken over by the large closed portion of the posterior pallia! oviduct. A spermatophore bursa in the outer or inner laminae of the palliai oviduct is a common feature in most cerithiids and its absence in Fastigiella is noteworthy. This palliai oviduct is very similar to those described for many cerithiids, potamidids, and Diastoma (see Houbrick, 1974, 1978, 1981b). The posterior end of the palliai oviduct is closed by fusion of the edges of the two laminae (figure 21, f). The palliai oviduct of Fastig- iella differs from all other known cerithiacean pallia] oviducts in having a large, swollen central ridge (figure 21, rd) at the base of the anterior oviductal groove. This ridge diminishes in size and disappears about midway along the palliai oviduct effectively forming two anterior oviductal grooves that merge past the middle of the palliai oviduct to form the main posterior oviductal groove. The function of this apomorphic structure is un- known. The ovary is large and differs from other ob- served cerithiid ovaries in being highly acinous. Males remain unknown but, on the basis of female anatomy, are expected to be aphallate and have open palliai gon- oducts. The alimentary tract is indicative of a microphagous, herbivorous mesogastropod. The short radula is different from that of most cerithiids in having long lateral teeth with conspicuous platelike lateral extensions (figure 16) and long hooklike marginals with microscopic serrations near their tips (figure 15). Similar lateral and marginal teeth occur in the cerithiids Clavocerithium taeniatum (Quoy & Gaimard) and Rhinoclavis sordidula (Gould) (Houbrick, 1975:101, figs. 9-12; 1978:71, pi. 40). Some planaxid radulae have similar lateral teeth (Houbrick, 1987). Although the salivary glands, or at least the left salivary gland, pass through the nerve ring in most cer- ithiids, the salivary glands of Fastigiella originate in front of the nerve ring. The esophagus widens behind the nerve ring, but there is no trace of an esophageal gland. A large dorsal food groove is present. The large, complex stomach with its extensive sorting area and large, raised central ridge (pad) is not unlike stomachs described for many other cerithiacean taxa. The number of openings to the digestive gland was not ascertained. CONCLUSIONS On the basis of the presence of a taenioglossate radula, proboscis structure and alimentary tract anatomy, we can confidently state that Fastigiella is a mesogastropod (order Caenogastropoda Cox, 1959). The open palliai oviduct and internal arrangement of the seminal recep- tacle and spermatophore ? bursa in the medial lamina strongly support an assignment to the superfamily Cer- ithiacea. Other external anatomical structures such as the head and snout, fringed mantle edge, corneous, ovate, paucispiral operculum, and propodial mucus gland are characters common in many cerithiacean families. In- ternal anatomical structures of the alimentary tract are likewise consistent with the cerithiacean anatomical or- ganization. Most characters, including those of the shell, indicate the family Cerithiidae as a suitable assignment for Fas- tigiella. Ontogenetic shell characters and a few anatom- ical characters suggest a close relationship to the genus Pseudovertagus Vignal, 1904. The unusual shell sculp- ture of three or four main spiral cords per whorl on the post-nuclear and upper whorls of Fastigiella is very sim- ilar to that seen in Pseudovertagus species. The broad snout is a character shared with Pseudovertagus. The hypobranchial gland comprised of transverse leaflets is likewise a synapomorphous character found only in Pseudovertagus and Fastigiella. The pseudumbilicus and siphonal fasciole with one to three false umbilical chinks formed by cord interspaces in large shells are autapomorphic characters clearly de- fining Fastigiella. Other shell characters identifying the axon are the strong spiral sculpture of three or four rounded cords per whorl, and the short, slightly reflected siphonal canal. The unusual, large ridge bisecting the anterior ovi- ductal groove of the palliai oviduct is an autapomorphy that sets Fastigiella aside as a good genus. Other non- apomorphic anatomical characters including placement and origin of the salivary glands anterior to the nerve ring, the shape of the lateral and marginal teeth, and the unusual leaflets of the hypobranchial gland, are more equivocal, but together provide a distinctive set of char- acters defining this taxon as a separate genus. No radular or anatomical characters have emerged from this study to suggest that Fastigiella should be given a higher than generic status. Fastigiella is a relictual, and geographically disjunct genus (at least on the basis of available material). We assign this genus in the Cer- ithiidae, close to the genus Pseudovertagus. Although it is unlikely that this assignment is incorrect, further study of males, other females, eggs, and larvae may provide more characters supportive of this classification. The sys- tematic position advocated herein is based on knowledge of a single female snail and is tentative until more is known about this rare animal. ACKNOWLEDGEMENTS We appreciate loans of material and useful information from James Cordy, Merritt Id., Florida; Dieter Cosman, Ft. Lauderdale, Florida; C. John Finlay, Palm Bay, Flor- ida; Joseph V. Lleida, Nassau, Bahamas; William G. Lyons, Marine Research Laboratory, St. Petersburg, Page 110 THE NAUTILUS, Vol. 101, No. 3 Florida; Lois F. McNeil, Plymouth Meeting, Pennsyl- vania; Marilee McNeilus, Eleuthera, Bahamas, and Dodge Center, Minnesota; Gary Rosenberg, Museum of Com- parative Zoology, Harvard University, Cambridge, Mas- sachusetts; Jack VVorsfold, Freeport, Grand Bahama Id., Bahamas. Photography was done by Mr. Victor Krantz, Smithsonian Photographic Services. R?diger Bieler, Smithsonian Marine Station, Link Port, Florida, and Pau- la Mikkelsen, Harbor Branch Oc?anographie Institution, Ft. Pierce, Florida, critically read drafts of the manu- script. LITERATURE CITED Abbott, R. T. 1974. American seashells, 2nd ed. New York, 663 p., 24 pis. Abbott, R. T. and P. Dance. 1982. Compendium of seashells. New York, 411 p., illus. Adams, H. and A. Adams. 18.53-58. The genera of Recent Moilusca, 3 voJs. London, 389 p., 138 pis. Chenu, J. C. 1859. Manuel de conchyliologie et de pal?on- tologie. Vol. 1. Paris, 508 p., 3707 figs. Cossmann, M. 1906. Essais de pal?oconchologie compar?e. Vol. 7. Pans, 261 p., 14 pis. Cox, L. R. 1960. Thoughts on the classification of the Gas- tropoda. Proceedings of the Malacological Society of Lon- don 33(6):239-261. Fischer, P. 1880-87. Manuel de conchyfiologie et de pal?on- tologie conchyliologique. Paris, 1369 p., 23 pis., 1158 figs. Ford, P. D. 1944. A complete list of Bahamian shells collected and classified by the Bahamas Conchological Society. Pri- vately published, Nassau, Bahamas, lip. Houbrick, R. S. 1974. The genus Cerithium in the western Atlantic. Johnsonia 5(50):33-84. Houbrick, R. S. 1975. Clavocerithium {Indocerithium} tae- nia turn, a little-known and unusual cerithiid from New Guinea. The Nautilus 89(4):99-105. Houbrick, R. S. 1978. The family Cerithiidae in the bido- Pacific. Part 1: the genera Rhinodavis, Pseiidoverta^us and Clavocerilhium. Monographs of Marine Moilusca No. 1T30 p., 98 pis. Houbrick, R. S. 1981a. Anatomy, biology and systematics of Campanile sijmbolicum with reference to adaptive radia- tion of the Cerithiacea (Gastropoda: Prosobranchia). Mal- acologia 21{l-2):263-289. Houbrick, R. S. 1981b. Anatomy of Diastoma melanioides (Reeve, 1849) with remarks on the systematic position of the family Diastomatidae (Prosobranchia: Gastropoda). Proceedings of the Biological Society of Washington 94(2): 598-621. Houbrick, R. S. 1987. Anatomy, biology and phylogeny of the Planaxidae (Cerithiacea: Prosobranchia). Smithsonian Contributions to Zoology No. 445:57 p., 27 Bgs., 6 tables. Jaume, M. L. and H. Saras?a. 1943. Notas sobre moluscos marinos Cubanos. Revista de la Sociedad Malacologica "Carlos de la Torre" 1(2):52-61. Jensen, D. 1967. Fastigiella carinata, a little known species. New York Shell Club Notes 128:6-7, i fig. Kline, G. F. 1953. Another specimen of Fastigiella carinata Reeve. The Nautilus 66(3):142. Lamarck, J. B. 1804. Suite des m?moires sur les fossiles des environs de Paris. Annales du Vlus?um National d'Histoire Naturelle (Paris) 3:436-441. Moore, D. R. 1971. V\'hat is Fastigiella carinata? Mollusk Chaser, South Florida Shell Club 9(8):l-2. M?rch, O. A. L. 1877. Description d'une nouvelle especie du genre Fastigiella Reeve. Journal de Conchyliologie 25:207. P?rez Farfante, I. 1940. Adiciones a la liste de moluscos Cu- banos. Memorias de la Sociedad Cubana de la Historia Naturalia 14(l):69-73. Pilsbry, H. A. 1953. Fastigiella carinata Reeve, a little-known mollusk. The Nautilus 66(3):77-78. Poulsen, C. M. 1878. Catalogue of west India shells. Copen- hagen, 16 p. Reeve, L. A. 1848. On Fastigiella, a new genus of shells of the Lamarkian family Canal?fera. Proceedings of the Zoo- logical Society of London 16:14-15. Reeve, L. A. 1860. Elements of conchology, Vol. 1. London, 260 p., 21 pis. Saras?a, H. and J. Espinosa. 1977. Notas sobre el genero Antilliano Fastigiella (MoUusca: Mesogastropoda). Poey- ana 171:1-11. Thiele, J. 1929. Handbuch der systematischen VVeichtier- kunde. Band 1, Teil 1. Gustav Fischer, Jena, 376 p., 470 figs. Tryon, G. W, 1882. Manual of conchology, first series. Vol. 4. Philadelphia, p. .5-276, ,58 pis. Wenz, W. 1940. Gastropoda, 1. Handbuch der Palaozoologie, Band 4, Part 4:721-960, text figs. 2085-2787; 1943, Band 6, Part 1:770 p., text figs. .3417-4211. Borntrager, Berlin. Woodward, S. P. 1851. A manual of the Moilusca or a treatise of Recent and fossil shells. London, 338 p., figs., pis. Note added in proof: Another live specimen of Fastigiella was recently collected by Kevan Sunderland in Im depth on a patch reef, half buried on sand, at Marsh Harbour, Abaco, Bahamas.